1. Field of the Invention
The invention relates to a cutting tool, or a part of a cutting tool, such as a cutter plate for machining, for example.
2. Description of Related Art
processing other materials. For example, chips removed from the workpiece are deflected at the cutting edges and slide along the cutting surfaces under high pressure.
The wear conditions of the tool are indicated by defects of the cutting edge, as well as defects of the surface. On the one hand, the tool should have the greatest possible service life, but on the other hand it should provide the highest possible cutting output.
Cutting tools, which are provided with a wear-reducing coating, are known. The coatings have been produced by means of the CVD process (chemical vapor deposition) or by means of the PVD process (physical vapor deposition). EP 0 736 615 A2, for example, discloses a multi-layered coating with a total of four layers applied to a substrate. The layer directly adhering to the substrate is a layer of TiCxNyOz. The next following layer is preferably a titanium carbonitride layer of TiCxNy. This layer is deposited by means of the CVD process at a temperature between 1000xc2x0 C. and 1100xc2x0 C.
No information is provided for a production by means of the PVD process.
Other examples of coated cutting tools are described, e.g., in U.S. Pat. Nos. 4,490,191; 4,501,786; and 4,341,834.
Based on the above, it is the object of the invention to create a wear-resistant cutting tool, as well as an efficient process for its production.
This object is attained by means of the cutting tool or the cutter plate having a carbonitride coating, optionally containing a group IV metal or aluminum. The cutting tool (1) or cutter plate (3, 4) has a wear-reducing coating, which contains carbonitride (CyNz) in which the carbon and nitrogen atom form a covalent bond and wherein y/z is preferably at least 2.
The cutting tool is produced by means of a hybrid PVD process wherein the carbon and nitrogen are supplied by gases and not a target. The process for producing a cutting tool or a cutter plate, includes in a first step a basic body is given a desired shape, at least in its areas which are to be coated, including the functionally important edges and surfaces, after which the basic body is subjected to an atmosphere, which is at least partially ionized and contains carbon as well as nitrogen.